The risorius and the buccinator muscles assist in the retraction of the lips, as well as support entrapment of air within the oral cavity.
笑肌和颊肌
助
的收缩，
支撑了
腔的气体流通。
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精选 Others may be less so, like the buccinator, a muscle that attaches your cheek to your teeth, or the body's tiniest skeletal muscle, a one-millimeter-long tissue fragment called the stapedius that's nestled deep inside the ear.
其他
肌肉我们就比较陌生了，比如颊肌，这是
种把你脸颊连接到牙齿上肌肉，还有身体上最纤细骨骼肌，片
长组织材料，叫做镫骨肌，位于我们耳朵深处。
